I’m just dropping in on the group today; I haven’t read the whole book. But one thing that stuck out to me in the chapter I read is the fact that the authors claim that the limbic system in the center of the brain is more primitive and older from an evolutionary standpoint. It is where primal emotions like anger, aggression, and fear are seated. By contrast, the frontal lobes and the anterior cingulate just below it are considered younger from an evolutionary standpoint and are the places where empathy, reason, logic, and compassion reside.
The chapter likens these two parts of the brain–the inner primal and the front outer rational–to two wolves that fight inside of us. Which one wins depends on which one you feed. This description is of course ripe with theological parallel–flesh versus Spirit, the yetzer hara or evil inclination of rabbinic Judaism, the id versus the superego of Freud.
But one of the most interesting things in the chapter (7) was the sense that the emotions of anger and fear actually inhibit good thinking. Such negative emotions can apparently even damage the anterior cingulate. So Spock and the Stoics were half right. The negative emotions of anger and fear do apparently impair our ability to reason well. But they were wrong to try to do away with all emotion. Apparently compassion and empathy can coincide with good thinking.